/**
 * @file
 * ACD protocol definitions
 */

/*
 *
 * Copyright (c) 2007 Dominik Spies <kontakt@dspies.de>
 * Copyright (c) 2018 Jasper Verschueren <jasper.verschueren@apart-audio.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Author: Jasper Verschueren <jasper.verschueren@apart-audio.com>
 * Author: Dominik Spies <kontakt@dspies.de>
 */

#ifndef LWIP_HDR_PROT_ACD_H
#define LWIP_HDR_PROT_ACD_H

#ifdef __cplusplus
extern "C" {
#endif

/* RFC 5227 and RFC 3927 Constants */
#define PROBE_WAIT 1   /* second  (initial random delay)                    */
#define PROBE_MIN 1    /* second  (minimum delay till repeated probe)       */
#define PROBE_MAX 2    /* seconds (maximum delay till repeated probe)       */
#define PROBE_NUM 3    /*         (number of probe packets)                 */
#define ANNOUNCE_NUM 2 /*         (number of announcement packets)          */
#define ANNOUNCE_INTERVAL                                                      \
    2                    /* seconds (time between announcement packets)       */
#define ANNOUNCE_WAIT 2  /* seconds (delay before announcing)  */
#define MAX_CONFLICTS 10 /*         (max conflicts before rate limiting) */
#define RATE_LIMIT_INTERVAL                                                    \
    60 /* seconds (delay between successive attempts)       */
#define DEFEND_INTERVAL                                                        \
    10 /* seconds (minimum interval between defensive ARPs) */

/* ACD states */
typedef enum {
    /* ACD is module is off */
    ACD_STATE_OFF,
    /* Waiting before probing can be started */
    ACD_STATE_PROBE_WAIT,
    /* Probing the ipaddr */
    ACD_STATE_PROBING,
    /* Waiting before announcing the probed ipaddr */
    ACD_STATE_ANNOUNCE_WAIT,
    /* Announcing the new ipaddr */
    ACD_STATE_ANNOUNCING,
    /* Performing ongoing conflict detection with one defend within defend
       inferval */
    ACD_STATE_ONGOING,
    /* Performing ongoing conflict detection but immediately back off and
     * Release the address when a conflict occurs. This state is used for LL
     * addresses that stay active even if the netif has a routable address
     * selected. In such a case, we cannot defend our address */
    ACD_STATE_PASSIVE_ONGOING,
    /* To many conflicts occurred, we need to wait before restarting the
     * selection process */
    ACD_STATE_RATE_LIMIT
} acd_state_enum_t;

typedef enum {
    ACD_IP_OK, /* IP address is good, no conflicts found in checking state */
    ACD_RESTART_CLIENT, /* Conflict found -> the client should try again */
    ACD_DECLINE         /* Decline the received IP address (rate limiting)*/
} acd_callback_enum_t;

#ifdef __cplusplus
}
#endif

#endif /* LWIP_HDR_PROT_ACD_H */
